<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> <!--Converted with LaTeX2HTML 2002-2-1 (1.71) original version by: Nikos Drakos, CBLU, University of Leeds * revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan * with significant contributions from: Jens Lippmann, Marek Rouchal, Martin Wilck and others --> <HTML> <HEAD> <TITLE>6.4.1 Hammer projection (-Jh -JH)</TITLE> <META NAME="description" CONTENT="6.4.1 Hammer projection (-Jh -JH)"> <META NAME="keywords" CONTENT="GMT_Docs"> <META NAME="resource-type" CONTENT="document"> <META NAME="distribution" CONTENT="global"> <META NAME="Generator" CONTENT="LaTeX2HTML v2002-2-1"> <META HTTP-EQUIV="Content-Style-Type" CONTENT="text/css"> <LINK REL="STYLESHEET" HREF="GMT_Docs.css"> <LINK REL="next" HREF="node115.html"> <LINK REL="previous" HREF="node113.html"> <LINK REL="up" HREF="node113.html"> <LINK REL="next" HREF="node115.html"> </HEAD> <BODY bgcolor="#ffffff"> <!--Navigation Panel--> <A NAME="tex2html4224" HREF="node115.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next.png"></A> <A NAME="tex2html4218" HREF="node113.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up.png"></A> <A NAME="tex2html4212" HREF="node113.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="prev.png"></A> <A NAME="tex2html4220" HREF="node1.html"> <IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" SRC="contents.png"></A> <A NAME="tex2html4222" HREF="node256.html"> <IMG WIDTH="43" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="index" SRC="index.png"></A> <BR> <B> Next:</B> <A NAME="tex2html4225" HREF="node115.html">6.4.2 Mollweide projection (-Jw</A> <B> Up:</B> <A NAME="tex2html4219" HREF="node113.html">6.4 Miscellaneous projections</A> <B> Previous:</B> <A NAME="tex2html4213" HREF="node113.html">6.4 Miscellaneous projections</A> <B> <A NAME="tex2html4221" HREF="node1.html">Contents</A></B> <B> <A NAME="tex2html4223" HREF="node256.html">Index</A></B> <BR> <BR> <!--End of Navigation Panel--> <H2><A NAME="SECTION001441000000000000000"> 6.4.1 Hammer projection (<B>-Jh</B> <B>-JH</B>)</A> </H2> <P> <A NAME="22556"></A> <A NAME="22557"></A> <A NAME="22558"></A> <P> The equal-area Hammer projection, first presented by the German mathematician Ernst von Hammer in 1892, is also known as Hammer-Aitoff (the Aitoff projection looks similar, but is not equal-area). The border is an ellipse, equator and central meridian are straight lines, while other parallels and meridians are complex curves. The projection is defined by selecting: <P> <UL> <LI>The central meridian [Middle of your map]. </LI> <LI>Scale along equator in inch/degree or 1:xxxxx (<B>-Jh</B>), or map width (<B>-JH</B>). </LI> </UL> <P> A view of the Pacific ocean using the Dateline as central meridian is accomplished thus <P> <BR CLEAR="ALL"> <HR> <BR> <PRE>pscoast -Rg -JH4.5i -Bg30/g15 -Dc -A10000 -Gblack -P > GMT_hammer.ps </PRE> <BR CLEAR="ALL"> <HR> <DIV ALIGN="CENTER"><A NAME="fig:GMT_hammer"></A><A NAME="23167"></A> <TABLE> <CAPTION ALIGN="BOTTOM"><STRONG>Figure 6.25:</STRONG> World map using the Hammer projection.</CAPTION> <TR><TD> <DIV ALIGN="CENTER"><IMG WIDTH="520" HEIGHT="261" ALIGN="BOTTOM" BORDER="0" SRC="img145.png" ALT="\includegraphics{scripts/GMT_hammer}"></DIV></TD></TR> </TABLE> </DIV> <P> <A NAME="22559"></A> <A NAME="22560"></A> <A NAME="22561"></A> <P> <HR> <!--Navigation Panel--> <A NAME="tex2html4224" HREF="node115.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next.png"></A> <A NAME="tex2html4218" HREF="node113.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up.png"></A> <A NAME="tex2html4212" HREF="node113.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="prev.png"></A> <A NAME="tex2html4220" HREF="node1.html"> <IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" SRC="contents.png"></A> <A NAME="tex2html4222" HREF="node256.html"> <IMG WIDTH="43" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="index" SRC="index.png"></A> <BR> <B> Next:</B> <A NAME="tex2html4225" HREF="node115.html">6.4.2 Mollweide projection (-Jw</A> <B> Up:</B> <A NAME="tex2html4219" HREF="node113.html">6.4 Miscellaneous projections</A> <B> Previous:</B> <A NAME="tex2html4213" HREF="node113.html">6.4 Miscellaneous projections</A> <B> <A NAME="tex2html4221" HREF="node1.html">Contents</A></B> <B> <A NAME="tex2html4223" HREF="node256.html">Index</A></B> <!--End of Navigation Panel--> <ADDRESS> Paul Wessel 2010-07-14 </ADDRESS> </BODY> </HTML>