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Python 3: UnboundLocalError: local variable referenced before assignment [duplicate]
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Jakob BowyerJakob Bowyer
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how does multiplication differ for NumPy Matrix vs Array classes?
...find it more trouble than it's worth, though.
For arrays (prior to Python 3.5), use dot instead of matrixmultiply.
E.g.
import numpy as np
x = np.arange(9).reshape((3,3))
y = np.arange(3)
print np.dot(x,y)
Or in newer versions of numpy, simply use x.dot(y)
Personally, I find it much more read...
How do you make an array of structs in C?
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#include<stdio.h>
#define n 3
struct body
{
double p[3];//position
double v[3];//velocity
double a[3];//acceleration
double radius;
double mass;
};
struct body bodies[n];
int main()
{
int a, b;
for(a = 0; a < n; a++)
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Get column index from column name in python pandas
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388
Sure, you can use .get_loc():
In [45]: df = DataFrame({"pear": [1,2,3], "apple": [2,3,4], "or...
Creating an instance of class
What's the difference between lines 1 , 2 , 3 , 4?
3 Answers
3
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NameError: global name 'xrange' is not defined in Python 3
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You are trying to run a Python 2 codebase with Python 3. xrange() was renamed to range() in Python 3.
Run the game with Python 2 instead. Don't try to port it unless you know what you are doing, most likely there will be more problems beyond xrange() vs. range().
For the recor...
Maven 3 warnings about build.plugins.plugin.version
Since I updated to Maven 3 I get the following warning messages at each build :
7 Answers
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Shuffle two list at once with same order
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You can do it as:
import random
a = ['a', 'b', 'c']
b = [1, 2, 3]
c = list(zip(a, b))
random.shuffle(c)
a, b = zip(*c)
print a
print b
[OUTPUT]
['a', 'c', 'b']
[1, 3, 2]
Of course, this was an example with simpler lists, but the adaptation will be the same for your case.
Hope it ...
MySQL Insert into multiple tables? (Database normalization?)
...and put that $var in all the MySQL commands?"
Let me elaborate: there are 3 possible ways here:
In the code you see above. This
does it all in MySQL, and the
LAST_INSERT_ID() in the second
statement will automatically be the
value of the autoincrement-column
that was inserted in the first
stateme...