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Started programming on a ZX spectrum in the 80's and have moved through Assembly, Turbo Pascal, C++, C#, Fortran. My main area of focus is engineering and scientific computing like numerical methods and 3D graphics.


Apr
23
comment Numerical Differentiation using Numerical Methods
Are you interpolating the data points with nspline() ?
Apr
14
comment Limit is found using polar coordinates but it is not supposed to exist.
Ohhh, spinny graph!
Mar
30
comment Matrix Vector Multiplications
There are many cases where the two values are going to be equal. There is no proof of you are asking because the statement is not universally true.
Mar
26
comment homogeneous coordinates
Can you give an example calculation (without homogeneous coordinate) of what "project onto line" means to you.
Mar
26
answered homogeneous coordinates
Mar
24
awarded  Popular Question
Mar
18
comment Tricky trigonometry question (distance of a ship)
Is the earth flat? Also is the tilt from vertical or horizontal.
Mar
16
awarded  Notable Question
Feb
24
comment A continued fraction involving prime numbers
+1 I was curious myself and did a little math with the primes < 100,000. Excel gives 0.4323320871859030 which is off by the last two digits. Then I found this question.
Feb
22
comment A rod with density \delta(x) = x^2+2x lies on the x-axis between x= 0 and x= 2. Find the mass and center of mass of the rod
Yes, you are correct.
Feb
17
answered A rod with density \delta(x) = x^2+2x lies on the x-axis between x= 0 and x= 2. Find the mass and center of mass of the rod
Feb
13
comment Calculating the trace of the product of two matrices
Start by decomposing $A = L L^\top$ using a Cholesky decomposition with $L$ a lower diagonal matrix, and $B = \sum e_i e_j^\top$ with $e_i$ a unit vector with a 1 in the i-th element and zero elsewhere.
Feb
5
comment Find the equation of the plane that passes through a point and parallel to another plane
For completeness. In order to understand how to go from $A x+B y+C z = D$ to planar normal and location and back.
Feb
5
answered Find the equation of the plane that passes through a point and parallel to another plane
Feb
5
comment Find the equation of the plane that passes through a point and parallel to another plane
The title says find the line and the statement says find the plane. Which one is it?
Feb
2
awarded  Nice Answer
Jan
23
comment $1 + 1 + 1 +\cdots = -\frac{1}{2}$
Did you read the links? You cannot add a divergent series.
Jan
22
comment angle to cardinal direction
Because if atan2() comes up zero it means east and you want east to be 90°. Also when atan2() is -90° it means south and you want 180°. That is why you have 90-atan2().
Jan
20
revised Solve for $X$: $4+2X > 7$
fixed title to proper expression
Jan
20
comment angle to cardinal direction
See edit now for conversion to 0=North, 90=East, 180=South and 270=West.