lpDot does not use the coefficients in LpAffineExpression

[ytakashina]

Details for the issue

What did you do?

x = pd.Series(pl.LpVariable.dicts("x", range(5)), index=range(5))  # Series of LpVariable
y = 2 * x  # Series of LpAffineExpression
a = np.arange(5)

What did you expect to see?

>>> pl.lpDot(y, a) 
LpAffineExpression([(x_1, 2), (x_2, 4), (x_3, 6), (x_4, 8)])

What did you see instead?

>>> pl.lpDot(y, a)
LpAffineExpression([(x_1, 1), (x_2, 2), (x_3, 3), (x_4, 4)])

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I'm using python version:

• 2.7
• 3.4
• 3.5
• 3.6
• Other: 3.7

I installed PuLP via:

• pypi (python -m pip install pulp)
• github (python -m pip install -U git+https://github.com/coin-or/pulp)
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Did you also

• Tried out the latest github version: https://github.com/coin-or/pulp
• Searched for an existing similar issue: https://github.com/coin-or/pulp/issues?utf8=%E2%9C%93&q=is%3Aissue%20

[sdementen]

fyi, as a workaround you can use y @ a instead of lpDot

[frrad]

Should be fixed by #769

[ytakashina]

fixed, thx!