# cdxbasics
Collection of basic tools for Python development.
Install by
conda install cdxbasics -c hansbuehler
or
pip install cdxbasics
## dynaplot
Tools for dynamic (animated) plotting in Jupyer/IPython. The aim of the toolkit is making it easy to develop visualization with `matplotlib` which dynamically updates, for example during training with machine learing kits such as `tensorflow`. This has been tested with Anaconda's JupyterHub and `%matplotlib inline`.
Some users reported that the package does not work in some versions of Jupyter. In this case, please try setting `dynaplot.DynamicFig.MODE = 'canvas'`. I appreciate if you let me know whether this resolved
the problem.
#### Animated Matplotlib in Jupyter
See the jupyter notebook [notebooks/DynamicPlot.ipynb](https://github.com/hansbuehler/cdxbasics/blob/master/cdxbasics/notebooks/DynamicPlot.ipynb) for some applications.
![dynamic line plot](https://raw.githubusercontent.com/hansbuehler/cdxbasics/master/media/dynaplot.gif)
![dynamic 3D plot](https://raw.githubusercontent.com/hansbuehler/cdxbasics/master/media/dynaplot3D.gif)
# example
%matplotlib inline
import numpy as np
x = np.linspace(-5,5,21)
y = np.ramdom.normal(size=(21,5))
# create figure
from cdxbasics.dynaplot import figure
fig = figure() # equivalent to matplotlib.figure
ax = fig.add_subplot() # no need to specify row,col,num
l = ax.plot( x, y[:,0] )[0] # get fist line2D object
fig.render() # construct figure & draw graph
# animate
import time
for i in range(1,5):
time.sleep(1)
l.set_ydata( y[:,i] ) # update data
fig.render()
fig.close() # clear figure to avoid duplication
See example notebook for how to use the package for lines, confidence intervals, and 3D graphs.
#### Simpler sub_plot
The package lets you create sub plots without having to know the number of plots in advance: you do not need to specify `rol, col, num` when calling `add_subplot`. The underlying figure object will automatically arrange them on a grid for you.
# create figure
from cdxbasics.dynaplot import figure
fig = figure(col_size=4, row_size=4, col_num=3)
# equivalent to matplotlib.figure
ax = fig.add_subplot() # no need to specify row,col,num
ax.plot( x, y )
ax = fig.add_subplot() # no need to specify row,col,num
ax.plot( x, y )
...
fig.next_row() # another row
ax = fig.add_subplot() # no need to specify row,col,num
ax.plot( x, y )
...
fig.render() # draws the plots
#### Other features
There are a number of other functions to aid plotting
* `figure()` which returns a `DynamicFig` object:
Function to replace `matplotlib.figure` which will defer creation of the figure until the first call of `render()`. The effect is that we no longer need to provide the total number of rows and columns in advance - i.e. you won't need to call the equivalent of `fig.add_subplot(3,4,14)` but can just call `fig.add_subplot()`.
* Instead of `figsize` the function `figure()` accepts `row_size`, `col_size` and `col_nums` to dynamically generate an appropriate figure size.
Key member functions of `DynamicFig` are:
* `add_subplot` to add a new plot. No arguments needed.
* `next_row()` to skip to the next row.
* `render()` to draw the figure. When called the first time will create all the underlying matplotlib objects. Subsequent calls will re-draw the canvas if the figure was modified. See examples in https://github.com/hansbuehler/cdxbasics/blob/master/cdxbasics/notebooks/DynamicPlot.ipynb
* `close()` to close the figure. If not called, Jupyter creates an unseemly second copy of the graph when the current cell is finished running.
* `color_css4, color_base, color_tableau, color_xkcd`:
Each function returns the $i$th element of the respective matplotlib color
table. The purpose is to simplify using consistent colors accross different plots.
Example:
fig = dynaplot.figure()
ax = fig.add_subplot()
# draw 10 lines in the first sub plot, and add a legend
for i in range(10):
ax.plot( x, y[i], color=color_css4(i), label=labels[i] )
ax.legend()
# draw 10 lines in the second sub plot. No legend needed as colors are shared with first plot
ax = fig.add_subplot()
for i in range(10):
ax.plot( x, z[i], color=color_css4(i) )
fig.render()
* `colors_css4, colors_base, colors_tableau, colors_xkcd`:
Generator versions of the `color_` functions.
## prettydict
A number of simple extensions to standard dictionaries which allow accessing any element of the dictionary with "." notation. The purpose is to create a functional-programming style method of generating complex objects.
from cdxbasics.prettydict import PrettyDict
pdct = PrettyDict(z=1)
pdct['a'] = 1 # standard dictionary write access
pdct.b = 2 # pretty write access
_ = pdct.b # read access
_ = pdct("c",3) # short cut for pdct.get("c",3)
There are three versions:
* `PrettyDict`:
Pretty version of standard dictionary.
* `PrettyOrderedDict`:
Pretty version of ordered dictionary.
* `PrettySortedDict`:
Pretty version of sorted dictionary.
#### Assigning member functions
"Pretty" objects also allow assigning bona fide member functions by a simple semantic of the form:
def mult_b( self, x ):
return self.b * x
pdct = mult_a
Calling `pdct.mult_a(3)` with above config will return `6` as expected. This only works when using the member synthax for assigning values
to a pretty dictionary; if the standard `[]` operator is used then functions will be assigned to the dictionary as usual, hence they are static members of the object.
The reason for this is as follows: consider
def mult( a, b ):
return a*b
pdct.mult = mult
mult(3,4) --> produces am error as three arguments as are passed if we count 'self'
In this case, use:
pdct['mult'] = mult
pdct.mult(3,4) --> 12
## config
Tooling for setting up program-wide configuration. Aimed at machine learning programs to ensure consistency of code accross experimentation.
from cdxbasics.config import Config
config = Config()
**Key features**
* Detect misspelled parameters by checking that all parameters of a config have been read.
* Provide summary of all values read, including summary help for what they were for.
* Nicer synthax than dictionary notation, in particular for nested configurations.
* Simple validation to ensure values are within a given range or from a list of options.
#### Creating configs
Set data with both dictionary and member notation:
config = Config()
config['features'] = [ 'time', 'spot' ]
config.weights = [ 1, 2, 3 ]
Create sub configurations with member notation
config.network.depth = 10
config.network.activation = 'relu'
config.network.width = 100
This is equivalent to
config.network = Config()
config.network.depth = 10
config.network.activation = 'relu'
config.network.width = 100
#### Reading a config
When reading the value of a `key` from config, `config.__call__()` uses a default value, and a cast type. It first attempts to find `key` in the `config`.
* If `key` is found, it casts the value provided for `key` using the `cast` type and returned.
* If `key` is not found, then the default value will be cast using `cast` type and returned.
The function also takes a `help` text which allows providing live information on what variable are read from the config. The latter is used by the function `usage_report()` which therefore provides live documentation of the code which uses the config object.
class Network(object):
def __init__( self, config ):
# read top level parameters
self.features = config("features", [], list, "Features for the agent" )
self.weights = config("weights", [], np.asarray, "Weigths for the agent", help_default="no initial weights")
config.done() # see below
In above example any data provided for they keywords `weigths` will be cast using `numpy.asarray`.
Further parameters of `()` are the help text, plus ability to provide text versions of the default with `help_default` (e.g. if the default value is complex), and the cast operator with `help_cast` (again if the
respective operation is complex).
__Important__: the `()` operator does not have a default value unless specified. If no default value is specified, and the key is not found, then a KeyError is generated.
You can read sub-configurations with the previsouly introduced member notation:
self.activation = config.network("activation", "relu", str, "Activation function for the network")
An alternative is the explicit:
network = config.network
self.depth = network('depth', 10000, int, "Depth for the network")
#### Imposing simple restrictions on values
We can impose simple restrictions to any values read from a config. To this end, import the respective type operators:
from cdxbasics.config import Int, Float
One-sided restriction:
# example enforcing simple conditions
self.width = network('width', 100, Int>3, "Width for the network")
Restrictions on both sides of a scalar:
# example encorcing two-sided conditions
self.percentage = network('percentage', 0.5, ( Float >= 0. ) & ( Float <= 1.), "A percentage")
Enforce the value being a member of a list:
# example ensuring a returned type is from a list
self.ntype = network('ntype', 'fastforward', ['fastforward','recurrent','lstm'], "Type of network")
We can allow a returned value to be one of several casting types by using tuples. The most common use case is that `None` is a valid value for a config, too. For example, assume that the `name` of the network model should be a string or `None`. This is implemented as
# example allowing either None or a string
self.keras_name = network('name', None, (None, str), "Keras name of the network model")
We can combine conditional expressions with the tuple notation:
# example allowing either None or a positive int
self.batch_size = network('batch_size', None, (None, Int>0), "Batch size or None for TensorFlow's default 32", help_cast="Positive integer, or None")
#### Ensuring that we had no typos & that all provided data is meaningful
A common issue when using dictionary-based code is that we might misspell one of the parameters. Unless this is a mandatory parameter we might not notice that we have not actually changed its value in the code below.
To check that all values of `config` are read use `done()`
config.done() # checks that we have read all keywords.
It will alert you if there are keywords or children which haven't been read. Most likely, those will be typos. Consider the following example where `width` is misspelled in our config:
class Network(object):
def __init__( self, config ):
# read top level parameters
self.depth = config("depth", 1, Int>=1, "Depth of the network")
self.width = config("width", 3, Int>=1, "Width of the network")
self.activaton = config("activation", "relu", help="Activation function", help_cast="String with the function name, or function")
config.done() # <-- test that all members of config where read
config = Config()
config.features = ['time', 'spot']
config.network.depth = 10
config.network.activation = 'relu'
config.network.widht = 100 # (intentional typo)
n = Network(config.network)
Since `width` was misspelled in setting up the config, you will get a warning to this end:
Error closing 'config.network': the following config arguments were not read: ['widht']
Summary of all variables read from this object:
config.network['activation'] = relu # Activation function; default: relu
config.network['depth'] = 10 # Depth of the network; default: 1
config.network['width'] = 3 # Width of the network; default: 3
Note that you can also call `done()` at top level:
class Network(object):
def __init__( self, config ):
# read top level parameters
self.depth = config("depth", 1, Int>=1, "Depth of the network")
self.width = config("width", 3, Int>=1, "Width of the network")
self.activaton = config("activation", "relu", help="Activation function", help_cast="String with the function name, or function")
config = Config()
config.features = ['time', 'spot']
config.network.depth = 10
config.network.activation = 'relu'
config.network.widht = 100 # (intentional typo)
n = Network(config.network)
test_features = config("features", [], list, "Features for my network")
config.done()
produces
ERROR:x:Error closing 'config.network': the following config arguments were not read: ['widht']
Summary of all variables read from this object:
config.network['activation'] = relu # Activation function; default: relu
config.network['depth'] = 10 # Depth of the network; default: 1
config.network['width'] = 3 # Width of the network; default: 3
#
config['features'] = ['time', 'spot'] # Default: 2
You can check the status of the use of the config by using the `not_done` property.
#### Detaching child configs and other Copy operations
You can also detach a child config, which allows you to store it for later use without triggering `done()` errors:
def read_config( self, confg ):
...
self.config_training = config.training.detach()
config.done()
`detach()` will mark he original child as 'done'. Therefore, we will need to call `done()` again, when we finished processing the detached child:
def training(self)
epochs = self.config_training("epochs", 100, int, "Epochs for training")
batch_size = self.config_training("batch_size", None, help="Batch size. Use None for default of 32" )
self.config_training.done()
Use `copy()` to make a bona fide copy of a child, without marking the source child as 'done'. `copy()` will return a config which shares the same status as the source object. If you want an "unused" copy, use `clean_copy()`. A virtual clone is created via `clone()`. A cloned config stores information on usage in the same place for the original object. Thiis is also the semantic of the copy constructor.
#### Self-recording all available configuration parameters
Once your program ran, you can read the summary of all values, their defaults, and their help texts.
print( config.usage_report( with_cast=True ) )
Prints:
config.network['activation'] = relu # (str) Activation function for the network; default: relu
config.network['depth'] = 10 # (int) Depth for the network; default: 10000
config.network['width'] = 100 # (int>3) Width for the network; default: 100
config.network['percentage'] = 0.5 # (float>=0. and float<=1.) Width for the network; default: 0.5
config.network['ntype'] = 'fastforward' # (['fastforward','recurrent','lstm']) Type of network; default 'fastforward'
config.training['batch_size'] = None # () Batch size. Use None for default of 32; default: None
config.training['epochs'] = 100 # (int) Epochs for training; default: 100
config['features'] = ['time', 'spot'] # (list) Features for the agent; default: []
config['weights'] = [1 2 3] # (asarray) Weigths for the agent; default: no initial weights
#### Calling functions with named parameters:
def create_network( depth=20, activation="relu", width=4 ):
...
We may use
create_network( **config.network )
However, there is no magic - this function will mark all direct members (not children) as 'done' and will not record the default values of the function `create_network`. Therefore `usage_report` will be somewhat useless. This method will still catch unused variables as "unexpected keyword arguments".
#### Unique ID
Another common use case is that we wish to cache some process in a complex operation. Assuming that the `config` describes all relevant parameters
we can use `config.unique_id()` to obtain a unique hash ID for the given config.
This can be used, for example, as file name for caching. See also `cdxbasics.subdir` below.
#### Advanced **kwargs Handling
The `Config` class can be used to improve `kwargs` handling.
Assume we have
def f(**kwargs):
a = kwargs.get("difficult_name", 10)
b = kwargs.get("b", 20)
We run the usual risk of somebody mispronouncing the parameter name which we would never know. Therefore we may improve upon the above with
def f(**kwargs):
kwargs = Config(kwargs)
a = kwargs("difficult_name", 10)
b = kwargs("b", 20)
kwargs.done()
If now a user calls `f` with a misspelled `config(difficlt_name=5)` an error will be raised.
Another pattern is to allow both `config` and `kwargs`:
def f( config=Config(), **kwargs):
kwargs = config.detach.update(kwargs)
a = kwargs("difficult_name", 10)
b = kwargs("b", 20)
kwargs.done()
## logger
Tools for defensive programming a'la the C++ ASSERT/VERIFY macros. Aim is to provide one line validation of inputs to functions with intelligible error messages:
from cdxbasics.logger import Logger
_log = Logger(__file__)
...
def some_function( a, ...):
_log.verify( a==1, "'a' is not one but %s", a)
_log.warn_if( a!=1, "'a' was not one but %s", a)
#### Member functions; mostly self-explanatory:
Exceptions independent of logging level
verify( cond, text, *args, **kwargs )
If cond is not met, raise an exception with util.fmt( text, *args, **kwargs ). This is the Python version of C++ VERIFY
throw_if(cond, text, *args, **kwargs )
If cond is met, raise an exception with util.fmt( text, *args, **kwargs )
throw( text, *args, **kwargs )
Just throw an exception with util.fmt( text, *args, **kwargs )
Unconditional logging
debug( text, *args, **kwargs )
info( text, *args, **kwargs )
warning( text, *args, **kwargs )
error( text, *args, **kwargs )
critical( text, *args, **kwargs )
throw( text, *args, **kwargs )
Verify-conditional functions
# raise an exception if 'cond' is not True
verify( cond, text, *args, **kwargs )
# print log message of respective level if 'cond' is not True
verify_debug( cond, text, *args, **kwargs )
verify_info( cond, text, *args, **kwargs )
verify_warning( cond, text, *args, **kwargs )
If-conditional functions
# raise an exception if 'cond' is True
throw_if( cond, text, *args, **kwargs )
# write log message if 'cond' is True
debug_if( cond, text, *args, **kwargs )
info_if( cond, text, *args, **kwargs )
warning_if( cond, text, *args, **kwargs )
# print message if 'cond' is True
prnt_if( cond, text, *args, **kwargs ) # with EOL
write_if( cond, text, *args, **kwargs ) # without EOL
## subdir
A few tools to handle file i/o in a transparent way, focusing on caching data. The key idea is to provide transparent, concise pickle access to the file system in a manner similar to dictionary access. Files managed by `subdir` also all have the same extension, which is `pck` by default.
#### Key pattern:
Our pattern assumes that each calcuation is determined by a number of parameters for which we can compute a unique (file) ID for caching results. Unique file IDs can be computed using `uniqueFileName48()`. Here is an example which assumes that `None` is not a valid return value for the underlying function code:
from cdxbasics.config import Config
from cdxbasics.subdir import SubDir, CacheMode, uniqueFileName48
def function_with_caching( config ):
# determine caching strategy
cache_mode = config.caching("mode", CacheMode.ON, CacheMode.MODES, "Caching strategy: " + CacheMode.HELP)
cache_dir = config.caching("directory", "caching", str, "Caching directory")
cache_id = config.function.unique_id(length=48)
# check whether we should delete any existing files
if cache_mode.delete:
cache_dir.delete(cache_id)
# read existing file, if desired and possible
data_of_my_function = cache_dir.read(cache_id) if cache_mode.read else None
# check whether we need to compute some data
if data_of_my_function is None:
....
data_of_my_function = .... use config.function for settings
....
# write back to disk
if cache_node.write:
cache_dir.write(cache_id, data_of_my_function)
return data_of_my_function
See also the example for `CacheMode` below.
#### Creating directories
You can create directories using the `SubDir` class. Simply write
subdir = SubDir("my_directory") # relative to current working directory
subdir = SubDir("./my_directory") # relative to current working directory
subdir = SubDir("~/my_directory") # relative to home directory
subdir = SubDir("!/my_directory") # relative to default temp directory
You can specify a parent for relative path names:
subdir = SubDir("my_directory", "~") # relative to home directory
Change the extension to `bin`
subdir = SubDir("~/my_directory;*.bin")
subdir = SubDir("~/my_directory", ext="bin")
subdir = SubDir("my_directory", "~", ext="bin")
You can also use the `()` operator to generate sub directories. This operator is overloaded: for a single argument, it creates a relative sub-directory:
parent = SubDir("~/parent")
subdir = parent("subdir")
Be aware that when the operator `()` is called with two arguments, then it reads files; see below.
You can obtain a list of all sub directories in a directory by using `subDirs()`.
#### I/O
##### Reading
To read the data contained in a file 'file.pck' in our subdirectory with extension 'pck' use either of the following
data = subdir.read("file") # returns the default if file is not found
data = subdir.read("file", default=None) # returns the default if file is not found
This function will return `None` by default if 'file' does not exist. You can make it throw an error by calling `subdir.read("file", throwOnError=True)` instead.
You can also use the `()` operator, in which case you must specify a default value (if you don't, then the operator will return a sub directory):
data = subdir("file", None) # returns None if file is not found
You can also use both member and item notation to access files. In this case, though, an error will be thrown if the file does not exist
data = subdir.file # raises AtttributeError if file is not found
data = subdir['file'] # raises KeyError if file is not found
You can read a range of files in one function call:
data = subdir.read( ["file1", "file2"] )
Finally, you can also iterate through all existing files:
for file in subdir:
data = subdir.read(file)
...
To obtain a list of all files in our directory which have the correct extension, use `keys()`.
##### Writing
To write data, use any of
subdir.write("file", data)
subdir.file = data
subdir['file'] = data
To write several files at once, write
subdir.write(["file1", "file"], [data1, data2])
##### Test existence of files
To test existence of 'file' in a directory, use one of
subdir.exist('file')
'file' in subdir
#### Deleting files
To delete a 'file', use any of the following:
subdir.delete(file)
del subdir.file
del subdir['file']
All of these are _silent_, and will not throw errors if 'file' does not exist. In order to throw an error use
subdir.delete(file, raiseOnError=True)
Other file and directoru deletion methods:
* `deleteAllKeys`: delete all files in the directory, but do not delete sub directories or files with extensions different to our own.
* `deleteAllContent`: delete all files with our extension, and all sub directories.
* `eraseEverything`: delete everything
## util
A collection of utility functions.
### uniqueHash
uniqueHash( *kargs, **kwargs )
uniqueHash32( *kargs, **kwargs )
uniqueHash48( *kargs, **kwargs )
uniqueHash64( *kargs, **kwargs )
Each of these functions returns a unique hash key for the arguments provided for the respective function. The functions *32,*48,*64 return hashes of the respective length, while `uniqueHash` returns the hashes of standard length. These functions will make an effort to robustify the hashes against Python particulars: for example, dictionaries are hashed with sorted keys.
**These functions will ignore all dictionary or object members starting with "`_`".** They also will by default not hash _functions_ or _properties_.
This is sometimes undesitable, for example when functions are configuration elements:
config = Config()
config.f = lambda x : x**2
To change this behavuour, use `uniqueHashExt( length : int, parse_functions : bool = False, parse_underscore : str = "nonee")` which returns a hash function of desired lengths with the option to parse elements starting with "`_`" as well.
### CacheMode
A simple enum-type class to help implement a standard caching pattern.
It implements the following decision matrix
| |on |gen |off |update |clear |readonly|
|----------------------------------------|------|------|--------|---------|--------|--------|
|load cache from disk if exists |x |x |- |- |- |x|
|write updates to disk |x |x |- |x |- |-|
|delete existing object |- |- |- |- |x |-|
|delete existing object if incompatible |x |- |- |x |x |-|
Typically, the user is allowed to set the desired `CacheMode` using a `Config` element. The corresponding `CacheMode` object then implements the properties `read`, `write`, `delete` and `del_incomp`.
Prototype code is to be implemented as follows:
def compute_cached( ..., cache_mode, cache_dir ):
unique_id = unqiueHash48( ... ) # compute a unique hash for the object
# delete existing cache if requested
if cache_mode.delete:
cache_dir.delete(unique_id)
# attempt to read cache
ret = cache_dir.read(unique_id) if cache_mode.read else None
# validate cache, e.g. is it of the right version
if not ret is None:
# validate that 'ret is a valid object
if not is_valid(ret):
if cache_model.del_incomp:
cache_dir.delete(unqiue_id)
ret = None
# compute new object if need be
if ret is None:
# compute new object
ret = ...
# write new object to disk
if cache_mode.write:
cache_dir.write(unique_id, ret)
return ret
### WriteLine
A simple utility class to manage printing in a given line with carriage returns (`\r`).
Essentially, it keeps track of the length what was printed so far at the current line. If a `\r` is encountered it will clear the rest of the line to avoid having residual text from the previous line.
Example 1 (how to use \r and \n)
write = WriteLine("Initializing...")
import time
for i in range(10):
time.sleep(1)
write("\rRunning %g%% ...", round(float(i+1)/float(10)*100,0))
write(" done.\nProcess finished.\n")
Example 2 (line length is getting shorter)
write = WriteLine("Initializing...")
import time
for i in range(10):
time.sleep(1)
write("\r" + ("#" * (9-i)))
write("\rProcess finished.\n")
### Misc
* `fmt()`: C++ style format function.
* `plain()`: converts most combinations of standards elements or objects into plain list/dict structures.
* `isAtomic()`: whether something is string, float, int, bool or date.
* `isFloat()`: whether something is a float, including a numpy float.
* `isFunction()`: whether something is some function.
* `bind()`: simple shortcut to bind function parameters, e.g.
def f(a, b, c):
pass
f_a = bind(f, a=1)
* `fmt_list()` returns a nicely formatted list, e.g. `fmt_list([1,2,3])` returns `1, 2 or 3`.
* `fmt_seconds()` returns string for seconds, e.g. `fmt_seconds(10)` returns `10s` while `fmt_seconds(61)` returns `1:00`.
* `fmt_big_number()` converts a large integer into an abbreviated string with `K`, `M`, `B` (or `G`) for example `fmt_big_number(12345)` returns `12.35K`. You can change from the default `B` for billions to `G` by using the `fmt_computer` keyword.
* `fmt_datetime()` returns a nicely formatted daytime code in natural order e.g. YYYY-MM-DD HH:SS. It returns the respective simplification if just a `date` or `time` is passed instead of a `datetime`.
* `is_jupyter()` tries to assess whether the current environment is a jupyer IPython environment.
This is experimental as it appears there is no safe way to do this. The current implemenentation checks whether the command which started the current process contains the string `jupyter`.
## np
A small number of statistical numpy functions which take a weight vector (distribution) into account, namely
* `mean(P,x,axis)` computes the mean of `x` using the distribution `P`. If `P` is None, it returns `numpy.mean(x,axis)`.
* `var(P,x,axis)` computes the variance of `x` using the distribution `P`. If `P` is None, it returns `numpy.var(x,axis)`.
* `std(P,x,axis)` computes the standard deviation of `x` using the distribution `P`. If `P` is None, it returns `numpy.std(x,axis)`.
* `err(P,x,axis)` computes the standard error of `x` using the distribution `P`. If `P` is None, it returns `numpy.std(x,axis)/sqrt(x.shape[axis])`.
Two further functions are used to compute binned statistics:
* `mean_bins(x,bins,axis,P)` computes the means of `x` over equidistant `bins` using the distribition `P`.
* `mean_std_bins(x,bins,axis,P)` computes the means and standard deviations of `x` over equidistant `bins` using the distribition `P`.
## verbose
**The `verbose` interface has changed in 0.2.36**
This module provides the `Context` utility class for printing 'verbose' information, with indentation depending on the detail level.
The basic idea is that the root context has level 0, with increasing levels for sub-contexts. When printing information, we can (a) limit printing up to a given level and (b) automatically indent the output to reflect the current level of detail.
* Create a `Context` model, and define its verbosity in its constructor, e.g. `all`, `none` or a number. A negative number means that no outout will be generated (`quiet`), while `None` means all output will be printed (`all`). Sub-contexts inherent verbosity from their parents.
* To write a text at current level to `stdout` use `write()`.
* To write a text at a sub-level use `report()`. You can also use the overloaded call operator.
* To create a sub-context, either call `sub()` or use the overloaded call operator.
Here is an example:
from cdxbasics.verbose import Context, quiet
def f_sub( num=10, context = quiet ):
context.report(0, "Entering loop")
for i in range(num):
context.report(1, "Number %ld", i)
def f_main( context = quiet ):
context.write( "First step" )
# ... do something
context.report( 1, "Intermediate step 1" )
context.report( 1, "Intermediate step 2\nwith newlines" )
# ... do something
f_sub( context=context(1) ) # call function f_sub with a sub-context
# ... do something
context.write( "Final step" )
print("Verbose=1")
context = Context(1)
f_main(context)
print("\nVerbose=2")
context = Context(2)
f_main(context)
print("\nVerbose='all'")
context = Context('all')
f_main(context)
print("\nVerbose='quiet'")
context = Context('quiet')
f_main(context)
Returns
Verbose=1
00: First step
01: Intermediate step 1
01: Intermediate step 2
01: with newlines
01: Entering loop
00: Final step
Verbose=2
00: First step
01: Intermediate step 1
01: Intermediate step 2
01: with newlines
01: Entering loop
02: Number 0
02: Number 1
02: Number 2
02: Number 3
02: Number 4
02: Number 5
02: Number 6
02: Number 7
02: Number 8
02: Number 9
00: Final step
Verbose='all'
00: First step
01: Intermediate step 1
01: Intermediate step 2
01: with newlines
01: Entering loop
02: Number 0
02: Number 1
02: Number 2
02: Number 3
02: Number 4
02: Number 5
02: Number 6
02: Number 7
02: Number 8
02: Number 9
00: Final step
Verbose='quiet'
The purpose of initializing functions usually with `quiet` is that they can be used accross different contexts without printing anything by default.