js functions for matricies (See related posts)

//js functions for matricies

function nr(a){
        return a.length
}

function nc(a){
        return a[0].length
}

function sayDimensions(a){
        s=nr(a)+'x'+nc(a)
        return s;
}

function mat2string(a){
        s='';
        s+='<table>'
        for(var i=0;i<nr(a);i++){
                s+='<tr>'
                for(var j=0;j<nc(a);j++){
                        s+='<td>'
                        s+=a[i][j]
                }
        }
        s+='</table>'
        return s;
}

function writeInLine(){
        document.write('<table border=8 bordercolor=black><tr>')
        for(var i=0;i<arguments.length;i++){document.write('<td>'+arguments[i])}
        document.write('</table>')
}

function somma(a,b){
        c=new Array(nr(a));
        for(var k=0;k<nr(a);k++){c[k]=new Array(nc(a))}
        for(var i=0;i<nr(a);i++){
                for(var j=0;j<nc(a);j++){
                        c[i][j]=a[i][j]+b[i][j]
                }
        }
        return c;
}

function diff( a, b){
        c=new Array(nr(a));
        for(var k=0;k<nr(a);k++){c[k]=new Array(nc(a))}
        for(var i=0;i<nr(a);i++){
                for(var j=0;j<nc(a);j++){
                        c[i][j]=a[i][j]-b[i][j]
                }
        }
        return c;
}

function pms( m, s){
        c=new Array(nr(m));
        for(var k=0;k<nr(m);k++){c[k]=new Array(nc(m))}
        for(var i=0;i<nr(m);i++){
                for(var j=0;j<nc(m);j++){
                        c[i][j]=s*m[i][j]
                }
        }
        return c;
}

function prodotto(a,b){
        c=new Array(nr(a));
        for(var k=0;k<nr(a);k++){c[k]=new Array(nc(b))}

        for(var i=0;i<nr(a);i++){
                for(var j=0;j<nc(b);j++){
                        c[i][j]=0;
                        for(var l=0;l<nr(b);l++){
                                c[i][j]+=a[i][l]*b[l][j]
                        }
                }
        }
        return c;
}