def tk03(n=100,dec=0,lat=0,rev='no',G2=0,G3=0):
"""
generates set of vectors drawn from the TK03.gad model of
secular variation at given latitude and rotated about vertical
axis by given declination
Parameters
----------
n number of vectors to determine (default is 100)
dec mean declination of data set (default is 0)
lat latitude at which secular variation is simulated (default is 0)
rev if reversals are to be included this should be 'yes' (default is 'no')
G2 specify average g_2^0 fraction (default is 0)
G3 specify average g_3^0 fraction (default is 0)
"""
tk_03_output=[]
for k in range(n):
gh=pmag.mktk03(8,k,G2,G3) # terms and random seed
long=random.randint(0,360) # get a random longitude, between 0 and 359
vec= pmag.getvec(gh,lat,long) # send field model and lat to getvec
vec[0]+=dec
if vec[0]>=360.:
vec[0]-=360.
if k%2==0 and rev=='yes':
vec[0]+=180.
vec[1]=-vec[1]
tk_03_output.append([vec[0],vec[1],vec[2]])
return tk_03_output
def main():
"""
NAME
tk03.py
DESCRIPTION
generates set of vectors drawn from TK03.gad at given lat and
rotated about vertical axis by given Dec
INPUT (COMMAND LINE ENTRY and interactive)
OUTPUT
dec, inc, int
SYNTAX
tk03.py [command line options] [> OutputFileName]
OPTIONS
-n N specify N, default is 100
-d D specify mean Dec, default is 0
-lat LAT specify latitude, default is 0
-rev include reversals
-t INT truncates intensities to >INT uT
-G2 FRAC specify average g_2^0 fraction (default is 0)
-G3 FRAC specify average g_3^0 fraction (default is 0)
"""
N,L,D,R=100,0.,0.,0
G2,G3=0.,0.
cnt=1
Imax=0
if len(sys.argv)!=0 and '-h' in sys.argv:
print main.__doc__
sys.exit()
else:
if '-n' in sys.argv:
ind=sys.argv.index('-n')
N=int(sys.argv[ind+1])
if '-d' in sys.argv:
ind=sys.argv.index('-d')
D=float(sys.argv[ind+1])
if '-lat' in sys.argv:
ind=sys.argv.index('-lat')
L=float(sys.argv[ind+1])
if '-t' in sys.argv:
ind=sys.argv.index('-t')
Imax=1e3*float(sys.argv[ind+1])
if '-rev' in sys.argv: R=1
if '-G2' in sys.argv:
ind=sys.argv.index('-G2')
G2=float(sys.argv[ind+1])
if '-G3' in sys.argv:
ind=sys.argv.index('-G3')
G3=float(sys.argv[ind+1])
for k in range(N):
gh=pmag.mktk03(8,k,G2,G3) # terms and random seed
long=random.randint(0,359) # get a random longitude, between 0 and 359
vec= pmag.getvec(gh,L,long) # send field model and lat to getvec
if vec[2]>=Imax:
vec[0]+=D
if k%2==0 and R==1:
vec[0]+=180.
vec[1]=-vec[1]
if vec[0]>=360.:vec[0]-=360.
print'%7.1f %7.1f %8.2f ' % (vec[0],vec[1],vec[2])