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<DIV><SPAN class=884110509-17092012><FONT color=#0000ff size=2 face=Arial>Hi
Paul,</FONT></SPAN></DIV>
<DIV><SPAN class=884110509-17092012><FONT color=#0000ff size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=884110509-17092012><FONT color=#0000ff size=2
face=Arial>Assuming the relationship between x, y and T is approximately linear,
then you can just match the points on the curves pairwise and interpolate
between the pairs using interpln. If your target temperature T is such
that T = aT1 + (1-a)T2, then it will produce a point at abscissa x = ax1 +
(1-a)x2 and ordinate y = ay1 + (1-a)y2, where (x1,y1) and (x2,y2) are one of the
pairs of points. You can build up the two x and y vectors and plot using
plot2d.</FONT></SPAN></DIV>
<DIV><SPAN class=884110509-17092012><FONT color=#0000ff size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=884110509-17092012><FONT color=#0000ff size=2 face=Arial>This
is usually only useful between your two temperatures (interpolation) and is of
limited accuracy outside (extrapolation), but that
depends...</FONT></SPAN></DIV>
<DIV><SPAN class=884110509-17092012><FONT color=#0000ff size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=884110509-17092012><FONT color=#0000ff size=2 face=Arial>If you
need to get the result on a defined abscissa grid, then you can interpolate in
the x and y directions separately, noting that sometimes it makes a difference
which order you do this in. Depending on the spacing of your x points, a
linear interpolation in the x direction may not be accurate enough. In
that case, I would use for example a Lagrange interpolation.</FONT></SPAN></DIV>
<DIV><SPAN class=884110509-17092012><FONT color=#0000ff size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=884110509-17092012><FONT color=#0000ff size=2
face=Arial>HTH,</FONT></SPAN></DIV>
<DIV><SPAN class=884110509-17092012><FONT color=#0000ff size=2
face=Arial>Mike.</FONT></SPAN></DIV>
<DIV><SPAN class=884110509-17092012><FONT color=#0000ff size=2
face=Arial></FONT></SPAN> </DIV>
<BLOCKQUOTE style="MARGIN-RIGHT: 0px" dir=ltr>
<DIV dir=ltr class=OutlookMessageHeader align=left><FONT size=2
face=Tahoma>-----Original Message-----<BR><B>From:</B>
users-bounces@lists.scilab.org [mailto:users-bounces@lists.scilab.org]<B>On
Behalf Of </B>Carrico, Paul<BR><B>Sent:</B> 17 September 2012
08:54<BR><B>To:</B> users@lists.scilab.org<BR><B>Subject:</B> [Scilab-users]
LInear interpolation between 2 curves<BR><BR></FONT></DIV>
<DIV><SPAN
style="FONT-FAMILY: 'Comic Sans MS'; COLOR: green; FONT-SIZE: 10pt"><SPAN
class=711212207-17092012><FONT color=#000000 face=Arial>Dear
all,</FONT></SPAN></SPAN></DIV>
<DIV><SPAN
style="FONT-FAMILY: 'Comic Sans MS'; COLOR: green; FONT-SIZE: 10pt"><SPAN
class=711212207-17092012><FONT color=#000000
face=Arial></FONT></SPAN></SPAN> </DIV>
<DIV><SPAN
style="FONT-FAMILY: 'Comic Sans MS'; COLOR: green; FONT-SIZE: 10pt"><SPAN
class=711212207-17092012><FONT color=#000000 face=Arial>Is it possible to make
a linear interpolation between 2 curves ? note the abscissa are not necessary
exactly the same ...</FONT></SPAN></SPAN></DIV>
<DIV><SPAN
style="FONT-FAMILY: 'Comic Sans MS'; COLOR: green; FONT-SIZE: 10pt"><SPAN
class=711212207-17092012><FONT color=#000000
face=Arial></FONT></SPAN></SPAN> </DIV>
<DIV><SPAN
style="FONT-FAMILY: 'Comic Sans MS'; COLOR: green; FONT-SIZE: 10pt"><SPAN
class=711212207-17092012><FONT color=#000000 face=Arial>In particular terms,
I've a curve one at temperature X and another one at température Y and I would
like to have (and to plot) temperature at temperature Z in-between X-Y ...
(see attachment)</FONT></SPAN></SPAN></DIV>
<DIV><SPAN
style="FONT-FAMILY: 'Comic Sans MS'; COLOR: green; FONT-SIZE: 10pt"><SPAN
class=711212207-17092012><FONT color=#000000
face=Arial></FONT></SPAN></SPAN> </DIV>
<DIV><SPAN
style="FONT-FAMILY: 'Comic Sans MS'; COLOR: green; FONT-SIZE: 10pt"><SPAN
class=711212207-17092012><FONT color=#000000 face=Arial>I had a look in
interp, interp1 and interpln but nothing sound useful for me ... Am I wrong
?</FONT></SPAN></SPAN></DIV>
<DIV><SPAN
style="FONT-FAMILY: 'Comic Sans MS'; COLOR: green; FONT-SIZE: 10pt"><SPAN
class=711212207-17092012><FONT color=#000000
face=Arial></FONT></SPAN></SPAN> </DIV>
<DIV><SPAN
style="FONT-FAMILY: 'Comic Sans MS'; COLOR: green; FONT-SIZE: 10pt"><SPAN
class=711212207-17092012><FONT color=#000000 face=Arial>Thanks for any
advice</FONT></SPAN></SPAN></DIV>
<DIV><SPAN
style="FONT-FAMILY: 'Comic Sans MS'; COLOR: green; FONT-SIZE: 10pt"><SPAN
class=711212207-17092012><FONT color=#000000
face=Arial></FONT></SPAN></SPAN> </DIV>
<DIV><SPAN
style="FONT-FAMILY: 'Comic Sans MS'; COLOR: green; FONT-SIZE: 10pt"><SPAN
class=711212207-17092012><FONT color=#000000
face=Arial>Paul</FONT></SPAN></SPAN></DIV><PRE>--------------------------------------------------------------------------------
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