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Questions - math

Invalid Reference $$this for mongo array reduce arithmetic operation in java

First of all here is project before reduce How you can see there is a list called "1" with 3 fields (zone, duration, type) I'm trying to reduce it and get the total sum of durations on 1_to...
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París

java

mongodb

math

reduce

Votes: 0

Answers: 1

Latest Answer

Not a perfect solution but I managed to get what i needed like this STEPS: 1- Convert "duration" to String 2- Reduce Array to a concatenated String separated with "," AggregationEx...
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París

Adding Matrix in sympy from a 2x2 to a 3x3

So im trying to add two matrixes together in sympy from a 2x2 matrix to a 3x3 matrix and im not really sure how to do it! What i want to achieve is this: Wanted Result By adding together: K1 and K2. B...
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Lopehert

python

math

sympy

numeric

symbolic-math

Votes: 0

Answers: 2

Latest Answer

If I'm not mistaken, this is "standard" notation for FEM-like stiffness matrices. This is how I would do it: import sympy as sy E, t = sy.symbols("E, t") K1 = sy.Matrix([[17.5*E*t,...
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Davide_sd

Resolve colliding rotated rectangles by moving along vector

I have a javascript program that places rectangles one at a time along walls in a room in counter-clockwise order. I use the coordinates of the rectangles corners for collision detection. It skips the...
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hermanboy07

javascript

math

collision

Votes: 0

Answers: 1

Latest Answer

Consider using of Separating Axis Theorem. Two boxes (polygons in wide sense) don't intersect, if there exists some axis parallel to some box side, separating boxes, so the lie at distinct sides of th...
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MBo

How can I get the first 5 numbers of a double

how can i only have the first 5 numbers in a double? 12345.6789 --> 12345 1.23456789 --> 1.2345 0.123456789 --> 0.1234 I have tried different things such as multiplying the number by the pow...
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Need_Not

java

math

double

Votes: 0

Answers: 4

Latest Answer

Using BigDecimal: move the decimal point to the right/left until only the desired number of (significant) digits are in front of the decimal point; set the scale to zero, that is, removed all digits ...
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user16320675

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