mumax runs incorrectly

[jiawen xu]

My program has been checked, there is no obvious error, but when running, there is a prompt as shown in the following figure, it is not clear where the specific problem occurs. Hope to get your help.

[Josh Lauzier]

Hi,

I believe the issue is when you set the magnetization. In (and also the following 6 lines)

m. setRegion(1, Uniform(sin(pi/36)*RandNorm(), sin(pi/36)*sqrt(1-(RandNorm()*RandNorm())), cos(pi/36)))

RandNorm() is not guaranteed to be < 1 in magnitude. The definition is a normally distributed float64 in the range [-math.MaxFloat64, +[math.MaxFloat64]] with standard normal distribution (mean = 0, stddev = 1)  (source). This will tend to be less than one, given the mean and standard definition, but some tails of the distribution extend beyond +/-1 . So you can end up taking the square root of a negative number. You can instead use Rand() instead of RandNorm(), which is between 0 and 1 only. Best, Josh L.

[jiawen xu]

Thank you very much for your help, it can run normally.