The assignments. DAB721 Computer Architecture. Today. PPM and PGM. PPM and PGM. The deal. Parallel programming. Image manipulation

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1 The assignments DAB721 Computer Architecture Introduction to ZPL Morgan Ericsson Parallel programming ZPL (today) MPI (later) Image manipulation Greyscale conversion Histogram Smoothing Today Introduction to the assignments The deal The assignment Introduction to ZPL What is ZPL Getting started ZPL and lots of examples PPM and PGM Format used for images in this course You should be able to load/save these formats Very simple formats ASCII readable (mostly) Raw and ASCII (we like it raw!) Uncompressed Lots of available tools NetPBM (/usr/local/netpbm) XV (/usr/local/bin) Etc (google!) The deal Everything you need is on the course page or linked to from the course page, except /stud/kurser/dab721 I introduce the assignment and the different techniques and environments and Daniel answers your questions and corrects/grade your (pratical) work/assignments (Don t bother me! ) PPM and PGM Format [MAGIC] # Optional comment [WIDTH] [HEIGHT] [MAXIMUM COLOR COMPONENT VALUE] Image data (RGB) * HEIGHT * WIDTH Height, width, etc, ASCII formated integers, i.e. 640 Magic identifies the format, P5 PGM RAW, P6 PPM RAW 1

2 Example P6 # CREATOR: XV Version 3.10a Rev: 12/29/ ^O^M^N^P^N^O^Q^Q^Q^Q^S^R^M^O^N ^M^L^N^T ^R^X^^ ^\ ^^$" &$#'&#'&%%%%%%&$%&&&%%'$%'$%'#$&#$&"#% #%"#% #$&$%'$%'%&(%&($%'$%'#$&"$##%$#%$$&%$&%#%$#%$"$#! #"!#""$##%$#%$"$#!#"!#""#%"#%"#%"#%"#%"#%"#%"#%#$ &$%'$%'$%'$%'#$&"#%!"$#%$#%$#%$$&%$&%%'&%'&%'&#%$ #%$#%$$&%$&%%'&%'&%'& ZPL Syntax very similar to Pascal (and Ada) Please note /* */ comments := assignment, = comparison ZPL High-level, platform independent Data Parallel Implicitly parallel Can be run in parallel or sequentially Array programming language Operations can be applied to arrays (of any dimension) program Ex1; Example 1 procedure Ex1(); writeln("hello, world!"); Getting started ZPL is installed in the Unix lab rooms Set the following envs: Set ZPLHOME to /opt/zplhome Set ZPLCOMMLAYER to seq Set ZPLTARGET to sparc-solaris (Syntax depending on shell, use setenv if csh) Or Run /stud/kurser/dab721/instmpi Then what? Compiler is zc Executables are named like the source, but without.z Example 2 program Ex2; a,b:integer; procedure Ex2(); b:=10; a:=a+b; a+=b;; writeln("a=",a,"."); write("a=%0d.\n":a); write("a=%0d":a, ", b=%0d.\n":b); 2

3 program Ex3; a,b,i:integer; procedure Ex3(); a:=0; for i:=1 to 5 do a+=i; writeln(a); Example 3 program Ex5; a: [R] integer; procedure Ex5(); Example 5 Example 4 Example 6 program Ex4; a,b:integer; procedure Ex4(); read(a); read(b); if a<b then writeln("a<b"); elsif a>b then writeln("a>b"); else writeln("a=b"); program Ex6; R2 = [3..6]; procedure Ex6(); [R2] a+=b; (Parallel) Arrays and Regions Regions = indices Used to declare arrays or specifiy regions that operations should operate on Example: a: [R] integer; Not first class objects! Directions Position-independant way of indexing arrays 3

4 Directions Definied by giving rules for transforming an index direction north = [-1, 0]; Parallel arrays can not be indexed in other ways Scans and Reductions Operations that calculates something based on the whole array Reductions reduces the array to a single value Scans propagate the values through the array A = [ 1, 3, 2 ] max<<a = 3 (R) max A = [ 1, 3, 3 ] (S) Region Operators Used to index/create new regions based on regions and/or directions of, creates a new region relative to a region and a direction at(@), indexing (displacement) by direction (can be used with iables as well) in, creates a new region inside another region Reductions Available reductions (scans similar) +<< *<< max<< min<< &<< (and) << (or) Example 7 Example 8 program Ex7; R2 = [3..6]; direction above = [+1]; below = [-1]; procedure Ex7(); [R2] a+=b; [above of R2] a:=99; [below of R2] a:=-100; program Ex8; m,s: integer; procedure Ex8(); [R] m:=max<<b; [R] s:=+<<b; [R] a:=+ a; 4

5 Config iables Can be used to set constants at runtime Array sizes or regions, for example executable siable=value./ex9 sn=5 Now what? Use the reference manual Try to understand the examples Not all available examples were used in this presentation File I/O (ex11) Experiment! Example 9 program Ex9; config n:integer = 10; region R = [1..n,1..n]; a: [R] integer; m,s: integer; procedure Ex9(); [R] a:=index1*index2; [R] m:=max<<a; [R] s:=+<<a; Records Composite types, like records are available type Name = record Definitions ;. is used to access values in a record (like Ada,C) myrecord.myinteger := 5; (See example 11 for more information) 5