tdms utilities

tdms snippets

tdms_file=TdmsFile.read(fpath)
for name, value in tdms_file.properties.items():
    print("{0}: {1}".format(name, value))
    
print ("------ Groups --------")
all_groups = tdms_file.groups()
for group in all_groups:
    print ("Group Name:",group.name)
    

print ("----------Group Details---------")
maxchannels=20
for group in all_groups:
    print ("Group Name:",group.name)
    print ("\t","Group Properties:","\t",group.properties)
    
    for ch in group.channels()[0:maxchannels]:
        print ("\t","Channel Name:",ch.name,":Channel Properties:", ch.properties)
    if (len(group.channels()) > maxchannels):
        print ("\t ....")
        for ch in group.channels()[-1*maxchannels:]:
            print ("\t","Channel Name:",ch.name,":Channel Properties:", ch.properties)
        


def tdms_print_contents (tdms_file):
    for group in tdms_file.groups() :
        print ("Group:" ,group.name)
        for channel in group.channels():
            print ("\t","Group:",group.name, ":","Channel:",channel.name)
            
def size_lv_flatten_to_string (data,dimension=0):
    """
    returns size of array strored by lv in preprend of flatten to string from array - single dim =[0..3], 
    2d array has two of these and so on. Single dimesnion is 0 not 1
    labview prepends with array size in tdms files by default
    """
    len1=channel.data[dimension*4:dimension*4+4]  # 0 is 0:4, 4:8
    len1 = len1[::-1] #reverse 
    len_bytes = np.array (len1, dtype=np.uint8) #convert to numpy array
    data_as_i32 = len_bytes.view(dtype=np.int32) 
    return (data_as_i32[0])

size_lv_flatten_to_string (channel.data,dimension=0) 


# --- doubles stored as bytes using flatten to string then stirng to byte in tdms
d2d = np.reshape(data, (x_array_size, y_array_size*8)) 
print ("Data 2d shape",d2d.shape)

d2d_as_dfloat = d2d.view(dtype='>f8') #use >f8 or <f8 to interpret the bytes as float64 with correct byte order
d2d_as_dfloat
print ("Data 2 d float shape",d2d_as_dfloat.shape)
y=d2d_as_dfloat[0]
y.shape


with TdmsFile.open("path_to_file.tdms"):
    channel = tdms_file[group_name][channel_name]
    channel_data = channel[:]
    

single_data = tdms_file['data']['xmult'][0] # group then channel


# explore tdms file groups channels

for name, value in tdms_file.properties.items():
    print("{0}: {1}".format(name, value))
all_groups = tdms_file.groups()
print ("------ Groups --------")
for group in all_groups:
    print ("Group Name:",group.name)
print ("----------Group Details---------")
maxchannels=20
for group in all_groups:
    print ("Group Name:",group.name)
    print ("\t","Group Properties:","\t",group.properties)
    
    for ch in group.channels()[0:maxchannels]:
        print ("\t","Channel Name:",ch.name,":Channel Properties:", ch.properties)
    if (len(group.channels()) > maxchannels):
        print ("\t ....")
        for ch in group.channels()[-1*maxchannels:]:
            print ("\t","Channel Name:",ch.name,":Channel Properties:", ch.properties)
       
# tdms_file[group_name][channel_name]
tdms_file['group name'].channels()