@TT_12301010 wrote:
The same program takes longer in mathcad prime10 than mathcad14.
This program uses arrays in particular.
So I got the following information:
"The most efficient way to use computer memory when using matrices is to pre-allocate the matrix. To do this, assign 0 to the last element of the matrix. This ensures that there is enough memory for the remaining elements of the matrix. If you dynamically allocate a matrix by filling in the elements of the matrix from the smallest subscript to the largest subscript, it will take longer to calculate and the worksheet will calculate slower."
But I don't know how to improve it.
Can someone please help me?
Translated by the moderation using Google Translate
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同じプログラムでmathcad14よりmathcad prime10のほうが時間がかかります。
このプログラムでは特に配列を使用しています。
そこで私は次の情報を得ました。
「行列を使用するときにコンピュータのメモリを最も効率的に使用する方法は、事前に行列を割り当てることです。このためには、行列の最後の要素に 0 を割り当てます。これによって、行列の残りの要素に十分なメモリが確保されます。一番小さな添字から一番大きな添字まで行列の要素を入力することで行列を動的に割り当てた場合、計算に時間がかかり、ワークシートの計算が遅くなります。」
しかし私はどのように改善すればよいかわかりません。
どなたかご協力お願いします。
You initialize the arrays by setting the element with estimated or known last index/indices to zero before assigning any values to the array. This minimizes the time Mathcad spends adding new elements to a dynamic array. For most purposes it makes little difference. However, it can give some time savings for large arrays. This was more of a problem with early versions of Mathcad running on the much slower PCs of the era.
Here are a couple of examples from your worksheet:
Some other small savings may be made by precalculating some of Fourier Transforms. When indexing CFFT(ee_in)j, for example, Mathcad will evaluate CFFT for each j.
Also note that CFFT is deprecated in Mathcad Prime 10, and it is recommended that it is replaced with dft.
"The new dft/idft functions replace the functionality of the deprecated cfft/icfft and CFFT/ICFFT functions and offer significant performance improvement, particularly for larger data sets and cases where the size is not a power of 2."
"Functions dft/idft differ from the deprecated fft/ifft, FFT/IFFT and cfft/icfft, CFFT/ICFFT in both the scaling factor and the exponent sign." - the scaling factor is now 1 for dft.
I hope that gives you a starting point for improving the worksheet's performance.
Stuart
