Groups > comp.graphics.apps.gnuplot > #3354

Strange Mobius strip in rendering a cylinder with pm3d

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Subject	Strange Mobius strip in rendering a cylinder with pm3d
From	musiphil@bawi.org
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Hello group,

I have the following gnuplot script:

set palette rgbformula 22,13,-31  # optional
splot "data" using (3*cos($1)):(2*sin($1)):2:3 palette with pm3d notitle

where "data" is generated by the following program (made up for illustrative purposes):

#!/usr/bin/python
import math

T = 36
H = 36

for i in xrange(T + 1):
	t = (2.0 * i / T - 1) * math.pi
	for j in xrange(H):
		h = 1.0 * j / H
		print '%+.4f\t%.4f\t%.4f' % (t, h, h)
	print

The graph I get, https://snag.gy/52RVPv.jpg, is twisted strangely like a Mobius strip.
Is there anything I did wrong and could correct, or is it a bug in gnuplot?
(Tested on: gnuplot 5.0 patchlevel 0 on Mac OS X.)

Thank you.

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Thread

Strange Mobius strip in rendering a cylinder with pm3d musiphil@bawi.org - 2016-06-27 21:43 -0700
  Re: Strange Mobius strip in rendering a cylinder with pm3d Michael Okuntsov <okuntsov.mikhail@yandex.ru> - 2016-06-28 16:20 +0700
    Re: Strange Mobius strip in rendering a cylinder with pm3d musiphil@bawi.org - 2016-06-28 09:46 -0700
    Re: Strange Mobius strip in rendering a cylinder with pm3d musiphil@bawi.org - 2016-06-28 10:27 -0700
  Re: Strange Mobius strip in rendering a cylinder with pm3d Hans-Bernhard Bröker <HBBroeker@t-online.de> - 2016-06-29 00:04 +0200
    Re: Strange Mobius strip in rendering a cylinder with pm3d musiphil@bawi.org - 2016-07-03 18:47 -0700

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