simple-squiggle

A restricted subset of Squiggle
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csCumsum.js (769B)

      1 "use strict";
      2 
      3 Object.defineProperty(exports, "__esModule", {
      4   value: true
      5 });
      6 exports.csCumsum = csCumsum;
      7 
      8 /**
      9  * It sets the p[i] equal to the sum of c[0] through c[i-1].
     10  *
     11  * @param {Array}   ptr             The Sparse Matrix ptr array
     12  * @param {Array}   c               The Sparse Matrix ptr array
     13  * @param {Number}  n               The number of columns
     14  *
     15  * Reference: http://faculty.cse.tamu.edu/davis/publications.html
     16  */
     17 function csCumsum(ptr, c, n) {
     18   // variables
     19   var i;
     20   var nz = 0;
     21 
     22   for (i = 0; i < n; i++) {
     23     // initialize ptr @ i
     24     ptr[i] = nz; // increment number of nonzeros
     25 
     26     nz += c[i]; // also copy p[0..n-1] back into c[0..n-1]
     27 
     28     c[i] = ptr[i];
     29   } // finalize ptr
     30 
     31 
     32   ptr[n] = nz; // return sum (c [0..n-1])
     33 
     34   return nz;
     35 }