src/negtranspose.js

/**
 * neg transpose
 * 
 * @export
 * @param {any} x
 * @returns
 */
export default function negtranspose(x) {
    var i,j,m = x.length,n = x[0].length, ret=Array(n),A0,A1,Bj;
    for(j=0;j<n;j++) ret[j] = Array(m);
    for(i=m-1;i>=1;i-=2) {
        A1 = x[i];
        A0 = x[i-1];
        for(j=n-1;j>=1;--j) {
            Bj = ret[j]; Bj[i] = -A1[j]; Bj[i-1] = -A0[j];
            --j;
            Bj = ret[j]; Bj[i] = -A1[j]; Bj[i-1] = -A0[j];
        }
        if(j===0) {
            Bj = ret[0]; Bj[i] = -A1[0]; Bj[i-1] = -A0[0];
        }
    }
    if(i===0) {
        A0 = x[0];
        for(j=n-1;j>=1;--j) {
            ret[j][0] = -A0[j];
            --j;
            ret[j][0] = -A0[j];
        }
        if(j===0) { ret[0][0] = -A0[0]; }
    }
    return ret;
}