def main():
nr = 5
nc = 6
nnodes = nr * nc
dx = 3
# instantiate grid
rg = RasterModelGrid(nr, nc, dx)
# rg.set_inactive_boundaries(False, True, True, False)
nodata_val = -1
z = nodata_val * np.ones(nnodes)
# set-up interior elevations with random numbers
# for i in range(0, nnodes):
# if rg.is_interior(i):
# elevations[i]=random.random_sample()
# set-up with prescribed elevations to test drainage area calcualtion
helper = [7, 8, 9, 10, 13, 14, 15, 16]
for i in range(0, len(helper)):
# print 'helper[i]', helper[i]
z[helper[i]] = 2 + uniform(-0.5, 0.5)
helper = [19, 20, 21, 22]
for i in range(0, len(helper)):
z[helper[i]] = 3 + uniform(-0.5, 0.5)
z[7] = 1
bc = WatershedBoundaryConditions()
bc.set_bc_find_outlet(rg, z, nodata_val)
# instantiate variable of type RouteFlowD8 Class
flow_router = RouteFlowD8(len(z))
# initial flow direction
flowdirs, max_slopes = flow_router.calc_flowdirs(rg, z)
# insantiate variable of type AccumFlow Class
accumulator = AccumFlow(rg)
# initial flow accumulation
drain_area = accumulator.calc_flowacc(z, flowdirs)
print("elevations ", rg.node_vector_to_raster(z))
print("flowdirs ", rg.node_vector_to_raster(flowdirs))
print("drain_area ", rg.node_vector_to_raster(drain_area))
def main():
nr = 5
nc = 6
nnodes = nr*nc
dx=3
#instantiate grid
rg = RasterModelGrid(nr, nc, dx)
#rg.set_inactive_boundaries(False, True, True, False)
nodata_val=-1
z = nodata_val*np.ones( nnodes )
#set-up interior elevations with random numbers
#for i in range(0, nnodes):
# if rg.is_interior(i):
# elevations[i]=random.random_sample()
#set-up with prescribed elevations to test drainage area calcualtion
helper = [7,8,9,10,13,14,15,16]
for i in range(0, len(helper)):
#print 'helper[i]', helper[i]
z[helper[i]]=2+uniform(-0.5,0.5)
helper = [19,20,21,22]
for i in range(0, len(helper)):
z[helper[i]]=3+uniform(-0.5,0.5)
z[7]=1
bc=WatershedBoundaryConditions()
bc.set_bc_find_outlet(rg, z, nodata_val)
#instantiate variable of type RouteFlowD8 Class
flow_router = RouteFlowD8(len(z))
#initial flow direction
flowdirs, max_slopes = flow_router.calc_flowdirs(rg,z)
#insantiate variable of type AccumFlow Class
accumulator = AccumFlow(rg)
#initial flow accumulation
drain_area = accumulator.calc_flowacc(z, flowdirs)
print("elevations ", rg.node_vector_to_raster(z))
print("flowdirs ", rg.node_vector_to_raster(flowdirs))
print("drain_area ", rg.node_vector_to_raster(drain_area))
def run_one_storm(self, grid, z, rainrate=None, storm_dur=None):
if rainrate==None:
rainrate = self.rainfall_myr
if storm_dur==None:
storm_dur = self.rain_duration_yr
m=self.m
n=self.n
K=self.K
frac = self.frac
#interior_nodes are the nodes on which you will be calculating incision
interior_nodes = np.where(grid.status_at_node != CLOSED_BOUNDARY)[0]
#instantiate variable of type RouteFlowD8 Class
flow_router = RouteFlowD8(len(z))
#initial flow direction
flowdirs, max_slopes = flow_router.calc_flowdirs(grid,z)
#print "elevations in runonestorm ",grid.node_vector_to_raster(z)
#insantiate variable of type AccumFlow Class
accumulator = AccumFlow(grid)
#initial flow accumulation
drain_area = accumulator.calc_flowacc(z, flowdirs)
time=0
dt = storm_dur
while time < storm_dur:
#Calculate incision rate, should be in m/yr, should be negative
#First make sure that there are no negative (uphill slopes)
#Set those to zero, because incision rate should be zero there.
max_slopes.clip(0)
I=-K*np.power(rainrate*drain_area,m)*np.power(max_slopes,n)
#print "incision rates ",grid.node_vector_to_raster(I)
#print "flow dirs ",grid.node_vector_to_raster(flowdirs)
#print "max slopes ",grid.node_vector_to_raster(max_slopes)
#print "drainage area ", grid.node_vector_to_raster(drain_area)
#Do a time-step check
#If the downstream node is eroding at a slower rate than the
#upstream node, there is a possibility of flow direction reversal,
#or at least a flattening of the landscape.
#Limit dt so that this flattening or reversal doesn't happen.
#How close you allow these two points to get to eachother is
#determined by the variable frac.
for i in interior_nodes:
dzdtdif = I[flowdirs[i]]-I[i]
if dzdtdif > 0:
dtmin = frac*(z[i]-z[flowdirs[i]])/dzdtdif
#Nic do you need a test here to make sure that dtmin
#isn't too small? Trying that out
if dtmin < dt:
if dtmin>0.001*dt:
dt = dtmin
else:
dt = 0.001*dt
#should now have a stable timestep.
#reduce elevations.
z=I*dt+z
#update elapsed time
time=dt+time
#check to see that you are within 0.01% of time
#if so, done
#otherwise, reset everything for next loop
if time > 0.9999*storm_dur:
#done!
time = storm_dur
else:
#not done, reset everything
#update time step to maximum possible
dt = storm_dur - time
#recalculate flow directions
flowdirs, max_slopes = flow_router.calc_flowdirs(grid,z)
#recalculate drainage area
drain_area = accumulator.calc_flowacc(z, flowdirs)
return z
def run_one_storm(self, grid, z, rainrate=None, storm_dur=None):
if rainrate == None:
rainrate = self.rainfall_myr
if storm_dur == None:
storm_dur = self.rain_duration_yr
m = self.m
n = self.n
K = self.K
frac = self.frac
#interior_nodes are the nodes on which you will be calculating incision
interior_nodes = np.where(grid.status_at_node != CLOSED_BOUNDARY)[0]
#instantiate variable of type RouteFlowD8 Class
flow_router = RouteFlowD8(len(z))
#initial flow direction
flowdirs, max_slopes = flow_router.calc_flowdirs(grid, z)
#print "elevations in runonestorm ",grid.node_vector_to_raster(z)
#insantiate variable of type AccumFlow Class
accumulator = AccumFlow(grid)
#initial flow accumulation
drain_area = accumulator.calc_flowacc(z, flowdirs)
time = 0
dt = storm_dur
while time < storm_dur:
#Calculate incision rate, should be in m/yr, should be negative
#First make sure that there are no negative (uphill slopes)
#Set those to zero, because incision rate should be zero there.
max_slopes.clip(0)
I = -K * np.power(rainrate * drain_area, m) * np.power(
max_slopes, n)
#print "incision rates ",grid.node_vector_to_raster(I)
#print "flow dirs ",grid.node_vector_to_raster(flowdirs)
#print "max slopes ",grid.node_vector_to_raster(max_slopes)
#print "drainage area ", grid.node_vector_to_raster(drain_area)
#Do a time-step check
#If the downstream node is eroding at a slower rate than the
#upstream node, there is a possibility of flow direction reversal,
#or at least a flattening of the landscape.
#Limit dt so that this flattening or reversal doesn't happen.
#How close you allow these two points to get to eachother is
#determined by the variable frac.
for i in interior_nodes:
dzdtdif = I[flowdirs[i]] - I[i]
if dzdtdif > 0:
dtmin = frac * (z[i] - z[flowdirs[i]]) / dzdtdif
#Nic do you need a test here to make sure that dtmin
#isn't too small? Trying that out
if dtmin < dt:
if dtmin > 0.001 * dt:
dt = dtmin
else:
dt = 0.001 * dt
#should now have a stable timestep.
#reduce elevations.
z = I * dt + z
#update elapsed time
time = dt + time
#check to see that you are within 0.01% of time
#if so, done
#otherwise, reset everything for next loop
if time > 0.9999 * storm_dur:
#done!
time = storm_dur
else:
#not done, reset everything
#update time step to maximum possible
dt = storm_dur - time
#recalculate flow directions
flowdirs, max_slopes = flow_router.calc_flowdirs(grid, z)
#recalculate drainage area
drain_area = accumulator.calc_flowacc(z, flowdirs)
return z
def main():
nr = 50
nc = 60
nnodes = nr*nc
dx=10
#instantiate grid
rg = RasterModelGrid(nr, nc, dx)
rg.set_inactive_boundaries(True, True, True, False)
z = np.zeros( nnodes )
#set-up interior elevations with random numbers
for i in range(0, nnodes):
if rg.is_interior(i):
z[i]=2+uniform(-0.5,0.5)
#some helper and parameter values
total_run_time = 10000 #yr
one_twentieth_time = total_run_time/20
uplift_rate = 0.001 #m/yr
rain_rate = 1 #m/yr
storm_duration = 50 #years
elapsed_time = 0 #years
#set up fluvial incision component
incisor = PowerLawIncision('input_file.txt',rg)
#print "elevations before ", rg.node_vector_to_raster(z)
#interior_nodes are the nodes on which you will be operating
interior_nodes = np.where(rg.status_at_node != CLOSED_BOUNDARY)[0]
while elapsed_time < total_run_time:
#erode the landscape
z = incisor.run_one_storm(rg,z,rain_rate,storm_duration)
#uplift the landscape
z[interior_nodes] = z[interior_nodes]+uplift_rate * storm_duration
#update the time
elapsed_time = elapsed_time+storm_duration
#print "elapsed_time", elapsed_time
if elapsed_time%one_twentieth_time == 0:
print("elapsed time",elapsed_time)
elev_raster = rg.node_vector_to_raster(z,True)
# Plot topography
pylab.figure(22)
im = pylab.imshow(elev_raster, cmap=pylab.cm.RdBu, extent=[0, nc*rg.dx, 0, nr*rg.dx])
cb = pylab.colorbar(im)
cb.set_label('Elevation (m)', fontsize=12)
pylab.title('Topography')
pylab.show()
#below purely for plotting reasons
#instantiate variable of type RouteFlowD8 Class
flow_router = RouteFlowD8(len(z))
#initial flow direction
flowdirs, max_slopes = flow_router.calc_flowdirs(rg,z)
#insantiate variable of type AccumFlow Class
accumulator = AccumFlow(rg)
#initial flow accumulation
drain_area = accumulator.calc_flowacc(z, flowdirs)
plt.loglog(np.array(drain_area),np.array(max_slopes),'ro',)
plt.xlabel('drainage area, m')
plt.ylabel('surface slope')
plt.show()
elev_raster = rg.node_vector_to_raster(z,True)
# Plot topography
pylab.figure(22)
im = pylab.imshow(elev_raster, cmap=pylab.cm.RdBu, extent=[0, nc*rg.dx, 0, nr*rg.dx])
cb = pylab.colorbar(im)
cb.set_label('Elevation (m)', fontsize=12)
pylab.title('Topography')
pylab.show()
def main():
nr = 5
nc = 6
nnodes = nr * nc
dx = 1
#instantiate grid
rg = RasterModelGrid(nr, nc, dx)
#rg.set_inactive_boundaries(False, True, True, False)
nodata_val = -1
z = nodata_val * np.ones(nnodes)
#set-up interior elevations with random numbers
#for i in range(0, nnodes):
# if rg.is_interior(i):
# elevations[i]=random.random_sample()
#set-up elevations
helper = [7, 8, 9, 10, 13, 14, 15, 16]
for i in range(0, len(helper)):
#print 'helper[i]', helper[i]
z[helper[i]] = 2 + uniform(-0.5, 0.5)
helper = [19, 20, 21, 22]
for i in range(0, len(helper)):
z[helper[i]] = 3 + uniform(-0.5, 0.5)
z[7] = 1
#set up boundary conditions
bc = WatershedBoundaryConditions()
outlet_loc = bc.set_bc_find_outlet(rg, z, nodata_val)
zoutlet = z[outlet_loc]
#some helper and parameter values
total_run_time = 500000 #yr
uplift_rate = 0.001 #m/yr
rain_rate = 1 #m/yr
storm_duration = 50 #years
elapsed_time = 0 #years
#set up fluvial incision component
incisor = PowerLawIncision('input_file.txt', rg)
#print "elevations before ", rg.node_vector_to_raster(z)
#interior_nodes are the nodes on which you will be operating
interior_nodes = np.where(rg.status_at_node != CLOSED_BOUNDARY)[0]
while elapsed_time < total_run_time:
#uplift the landscape
z[interior_nodes] = z[interior_nodes] + uplift_rate * storm_duration
z[outlet_loc] = zoutlet
#erode the landscape
z = incisor.run_one_storm(rg, z, rain_rate, storm_duration)
#update the time
elapsed_time = elapsed_time + storm_duration
#below purely for plotting reasons
#instantiate variable of type RouteFlowD8 Class
flow_router = RouteFlowD8(len(z))
#initial flow direction
flowdirs, max_slopes = flow_router.calc_flowdirs(rg, z)
#insantiate variable of type AccumFlow Class
accumulator = AccumFlow(rg)
#initial flow accumulation
drain_area = accumulator.calc_flowacc(z, flowdirs)
#m,b = polyfit(log10(drain_area[interior_nodes]), log10(max_slopes[interior_nodes]), 1)
z[interior_nodes] = z[interior_nodes] + uplift_rate * storm_duration
z[outlet_loc] = zoutlet
plt.loglog(
np.array(drain_area),
np.array(max_slopes),
'ro',
)
plt.show()
imshow_grid(rg, z, values_at='node')
def main():
nr = 5
nc = 6
nnodes = nr*nc
dx=1
#instantiate grid
rg = RasterModelGrid(nr, nc, dx)
#rg.set_inactive_boundaries(False, True, True, False)
nodata_val=-1
z = nodata_val*np.ones( nnodes )
#set-up interior elevations with random numbers
#for i in range(0, nnodes):
# if rg.is_interior(i):
# elevations[i]=random.random_sample()
#set-up elevations
helper = [7,8,9,10,13,14,15,16]
for i in range(0, len(helper)):
#print 'helper[i]', helper[i]
z[helper[i]]=2+uniform(-0.5,0.5)
helper = [19,20,21,22]
for i in range(0, len(helper)):
z[helper[i]]=3+uniform(-0.5,0.5)
z[7]=1
#set up boundary conditions
bc=WatershedBoundaryConditions()
outlet_loc = bc.set_bc_find_outlet(rg, z, nodata_val)
zoutlet=z[outlet_loc]
#some helper and parameter values
total_run_time = 500000 #yr
uplift_rate = 0.001 #m/yr
rain_rate = 1 #m/yr
storm_duration = 50 #years
elapsed_time = 0 #years
#set up fluvial incision component
incisor = PowerLawIncision('input_file.txt',rg)
#print "elevations before ", rg.node_vector_to_raster(z)
#interior_nodes are the nodes on which you will be operating
interior_nodes = np.where(rg.status_at_node != CLOSED_BOUNDARY)[0]
while elapsed_time < total_run_time:
#uplift the landscape
z[interior_nodes] = z[interior_nodes]+uplift_rate * storm_duration
z[outlet_loc]=zoutlet
#erode the landscape
z = incisor.run_one_storm(rg,z,rain_rate,storm_duration)
#update the time
elapsed_time = elapsed_time+storm_duration
#below purely for plotting reasons
#instantiate variable of type RouteFlowD8 Class
flow_router = RouteFlowD8(len(z))
#initial flow direction
flowdirs, max_slopes = flow_router.calc_flowdirs(rg,z)
#insantiate variable of type AccumFlow Class
accumulator = AccumFlow(rg)
#initial flow accumulation
drain_area = accumulator.calc_flowacc(z, flowdirs)
#m,b = polyfit(log10(drain_area[interior_nodes]), log10(max_slopes[interior_nodes]), 1)
z[interior_nodes] = z[interior_nodes]+uplift_rate * storm_duration
z[outlet_loc]=zoutlet
plt.loglog(np.array(drain_area),np.array(max_slopes),'ro',)
plt.show()
imshow_grid(rg,z, values_at='node')
