assembler compilation error!

I followed the SOPC builder tutorial which you can find in the link below:

http://www.usna.edu/ee/ee462/manuals/tut_sopc_introduction.pdf

I compiled the assembler code given in the tutorial:

.include "nios_macros.s"

.equ Switches, 0x00001800

.equ LEDs, 0x00001810

GFUNC _start

movia r2, Switches

movia r3, LEDs

loop: ldbio r4, 0(r2)

stbio r4, 0(r3)

br loop

BREAK

however I am gettting the compilation error as:-

Directory "C:\Asanka\Nios\lights\app_software\include" creaated!

Writing "system.h" in "C:\Asanka\Nios\lights\app_software\include" directory...

Cannot find the Altera University Program IP Cores path from registry. You may need to manually the configure SDK usage.

Compiling source files...

nios2-elf-as --gstabs -I C:/altera/61/nios2eds/components/altera_nios2/sdk/inc C:/Asanka/Nios/lights/app_software/lights.s -o C:/Asanka/Nios/lights/app_software/lights.s.o

/usr/bin/bash: nios2-elf-as: command not found

Linking...

nios2-elf-ld --defsym nasys_program_mem=0x0 --defsym nasys_data_mem=0x0 --section-start .exceptions=0x20 --section-start .reset=0x0 -e _start -u _start --script C:/altera/61/nios2eds/bin/monitor/build/nios_as_build.ld -g -o C:/Asanka/Nios/lights/app_software/lights.elf C:/Asanka/Nios/lights/app_software/lights.s.o

/usr/bin/bash: nios2-elf-ld: command not found

Compilation stopped.

can any body please help on why this error occured!