# code snippet resp. simplify and factor

this doesn't work

```
var('c')
mat=matrix([[1,0],[0,c]])
xy0=vector([c,1])
r0=-mat*xy0
p0=r0
for k in range(2):
la=r0*p0/(p0*mat*p0)
xy1=xy0+la*p0
print xy1
if xy1[0]!=0:
xy1[0]=xy1[0].factor()
if (xy1[1])!=0:
xy1[1]=xy1[1].factor()
print xy1
r1=(r0-la*mat*p0)
p1=r1+r1*r1/(r0.dot_product(r0))*p0
p1=p1.simplify_full()
p0=p1
r0=r1
xy0=xy1
print '--------------------'
```

but this works

```
var('c')
mat=matrix([[1,0],[0,c]])
xy0=vector([c,1])
r0=-mat*xy0
p0=r0
for k in range(2):
la=r0*p0/(p0*mat*p0)
xy1=xy0+la*p0
print xy1
xy1=xy1.simplify_full() # <<<<<<<<< inserted this command
if xy1[0]!=0:
xy1[0]=xy1[0].factor()
if (xy1[1])!=0:
xy1[1]=xy1[1].factor()
print xy1
r1=(r0-la*mat*p0)
p1=r1+r1*r1/(r0.dot_product(r0))*p0
p1=p1.simplify_full()
p0=p1
r0=r1
xy0=xy1
print '--------------------'
```

What is your question (or suggestion) ?