Cleanup TransferFunction input sanitization. #134

dapperfu · 2017-02-18T17:46:05Z

This started out to address #112 & #130, but I found a few other small edge cases.

To simplify unit testing I broke the input cleaning out to a separate function and added as many test cases as I could think of.

Deep copy

It performs a deep copy on args before anything else.

Test Code:

num = [[[1], [2]]]
den = [[[1,1], [2,1]]]
print(num)
print(den)
control.TransferFunction(num, den)
print(num)
print(den)

Before:

[[[1], [2]]]
[[[1, 1], [2, 1]]]
[[array([1]), array([2])]]
[[array([1, 1]), array([2, 1])]]

After:

[[[1], [2]]]
[[[1, 1], [2, 1]]]
[[[1], [2]]]
[[[1, 1], [2, 1]]]

Validate All Input Types:

The previous input validation would only check the first element if it was a valid input type. This means you could feed in extra bad values in other positions and it would accept it, only to fail later.

Test Code:

num = [[[1,"a"]]]
den = [[[2,1]]]
print(num)
print(den)
sys = control.TransferFunction(num, den)
print(num)
print(den)

Before:

It would accept the values (and mutate the inputs):

[[[1, 'a']]]
[[[2, 1]]]
[[array(['1', 'a'], 
      dtype='<U21')]]
[[array([2, 1])]]

But fail when you tried to access the system:

   1013 
   1014     for k in range(len(coeffs)):
-> 1015         coefstr = '%.4g' % abs(coeffs[k])
   1016         if coefstr[-4:] == '0000':
   1017             coefstr = coefstr[:-5]

TypeError: bad operand type for abs(): 'numpy.str_'

After

It fails immediately:

TypeError: The numerator and denominator inputs must be scalars or vectors (for
SISO), or lists of lists of vectors (for SISO or MIMO).

Added more valid types.

If you passed an numpy array as an input it would possibly fail depending on which architecture you were using it on. int resolves to int64 on 64-bit systems. It now accepts valid types of int, int8, int16, int32, int64, float, float16, float32, float64, float128. (If for some reason your transfer function parts were generated in another function).

Code:

import control
from numpy import array, int
num = array(1, dtype=int)
den = array([2, 1], dtype=int)
control.TransferFunction(num, den)

Before:

TypeError: The numerator and denominator inputs must be scalars or vectors (for
SISO), or lists of lists of vectors (for SISO or MIMO).

After:

    1
-------
2 s + 1

Added Tuple as valid collection for MIMO systems

It was easy enough to add and a valid ordered Python collection.

Given:

# Input 1 to Output 1
num11=[1]
den11=[2, 3]
# Input 1 to Output 2
num12=[4]
den12=[5, 6]
# Input 2 to Output 1
num21=[7]
den21=[8, 9]
# Input 2 to Output 2
num22=[10]
den22=[11, 12]

Previously this was the only valid MIMO input:

control.TransferFunction([[num11, num21],[num12, num22]], [[den11, den21],[den12, den22]])

Now all of these are also valid:

control.TransferFunction([(num11, num21),(num12, num22)], [(den11, den21),(den12, den22)])
control.TransferFunction(((num11, num21),(num12, num22)), ((den11, den21),(den12, den22)))
control.TransferFunction(([num11, num21],[num12, num22]), ([den11, den21],[den12, den22]))

Added IO cleanup function to xferfcn module.

From .eggs/README.txt: "This directory contains eggs that were downloaded by setuptools to build, test, and run plug-ins. This directory caches those eggs to prevent repeated downloads. However, it is safe to delete this directory."

…function. Added unit tests to test the cleanup function. Added deep copy to TransferFunction args.

coveralls · 2017-02-18T17:50:55Z

Coverage increased (+0.08%) to 77.408% when pulling 509ff8e on jed-frey:master into 5ab74cf on python-control:master.

coveralls · 2017-02-18T17:59:25Z

Coverage increased (+0.08%) to 77.408% when pulling 761bc2c on jed-frey:master into 5ab74cf on python-control:master.

coveralls · 2017-02-18T18:50:39Z

Coverage increased (+0.08%) to 77.408% when pulling c373f54 on jed-frey:master into 5ab74cf on python-control:master.

Jed added 5 commits February 17, 2017 13:57

Added notebook for doing development work on IO-Cleanup.

37b06f4

Added IO cleanup function to xferfcn module.

Added .eggs directory to gitignore.

feb68f5

From .eggs/README.txt: "This directory contains eggs that were downloaded by setuptools to build, test, and run plug-ins. This directory caches those eggs to prevent repeated downloads. However, it is safe to delete this directory."

Broke out the numerator/denominator cleanup function into a separate …

5e2d95d

…function. Added unit tests to test the cleanup function. Added deep copy to TransferFunction args.

Merge remote-tracking branch 'upstream/master'

cd7f596

Removed test notebook

509ff8e

Added Python 3.6

761bc2c

Removed Python 3.6

c373f54

dapperfu closed this Feb 18, 2017

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Cleanup TransferFunction input sanitization. #134

Cleanup TransferFunction input sanitization. #134

dapperfu commented Feb 18, 2017

coveralls commented Feb 18, 2017 •

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coveralls commented Feb 18, 2017 •

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coveralls commented Feb 18, 2017 •

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Cleanup TransferFunction input sanitization. #134

Cleanup TransferFunction input sanitization. #134

Conversation

dapperfu commented Feb 18, 2017

Deep copy

Before:

After:

Validate All Input Types:

Before:

After

Added more valid types.

Before:

After:

Added Tuple as valid collection for MIMO systems

coveralls commented Feb 18, 2017 • edited Loading

coveralls commented Feb 18, 2017 • edited Loading

coveralls commented Feb 18, 2017 • edited Loading

coveralls commented Feb 18, 2017 •

edited

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coveralls commented Feb 18, 2017 •

edited

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coveralls commented Feb 18, 2017 •

edited

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