<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div>Hi,</div><div><br></div><div>I hope the author of the SICP package is on this email list. I have encountered this problem doing affine transformation of the picture:</div><div><br></div><div><font face="Courier"> (paint ((transform-painter (make-vect 0 0) (make-vect 0.5 0.1) (make-vect 0 0.5)) einstein))</font></div><div><font face="Courier"><br></font></div><div><font face="Courier">. . ../../../../../../Library/Racket/planet/300/6.1/cache/soegaard/sicp.plt/2/1/prmpnt.scm:376:12: vector-ref: contract violation</font></div><div><font face="Courier"> expected: vector?</font></div><div><font face="Courier"> given: 0</font></div><div><font face="Courier"> argument position: 1st</font></div><div><font face="Courier"> other arguments...:</font></div><div><font face="Courier"> 2</font></div><div><font face="Courier"><br></font></div><div>If edge-2 vector is changed to (0 1), there is no problem:</div><div><br></div><div><font face="Courier">(paint ((transform-painter (make-vect 0 0) (make-vect 0.5 0.1) (make-vect <b>0 1</b>)) einstein))</font></div><div><font face="Courier"><br></font></div><div>Cheers,</div><div>Alexey</div></body></html>