Data Dictionary#
Output from TopoStats includes two sets of statistics in ASCII text .csv files. The tables below detail the columns of
these files, the data types, a description and their units where appropriate.
all_statistics.csv#
The all_statistics.csv file contains details on each grain that has been detected and traced and has the following fields.
The all_statistics.csv file contains details on each grain that has been detected and traced and has the following fields.
| Column / field / feature | Description | Type | Units |
|---|---|---|---|
image |
Filename (minus extension) of scan. | str |
N/A |
threshold |
Whether grain is above or below a threshold. |
str |
N/A |
molecule_number |
Number of found grain (starts at 0) |
int |
N/A |
centre_x |
x coordinate of grain centre. | float |
m |
centre_y |
y coordinate of grain centre. | float |
m |
radius_min |
minimum distance from the centroid to edge of the grain. | float |
m |
radius_max |
maximum distance from the centroid to edge of the grain. | float |
m |
radius_mean |
mean distance from the centroid to the edge of the grain. | float |
m |
radius_median |
median distance from the centroid to the edge of the grain. | float |
m |
height_min |
Minimum height of grain. | float |
m |
height_max |
Maximum height of grain. | float |
m |
height_median |
Median height of grain. | float |
m |
height_mean |
Mean height of grain. | float |
m |
volume |
Volume of the grain calculated as the number of pixels multiplied by each height and scaled to metres. | float |
m^3 |
area |
Area of the grain itself calculated as the number of pixels scaled to metres. | float |
m^2 |
area_cartesian_bbox |
Area of the bounding box for the grain along the cartesian axes. (Not the smallest bounding box). | float |
m^2 |
smallest_bounding_width |
Width of the smallest bounding box for the grain (not along cartesian axes). | float |
m |
smallest_bounding_length |
Length of the smallest bounding box for the grain (not along cartesian axes). | float |
m |
smallest_bounding_area |
Area of the smallest bounding box for the grain (not along cartesian axes). | float |
m^2 |
aspect_ratio |
Aspect ratio of the grain (length / width), always >= 1. | float |
N/A |
max_feret |
Longest length of the grain (see Feret diameter). | float |
m |
min_feret |
Shortest width of the grain (see Feret diameter). | float |
m |
contour_length |
UNKNOWN | float |
m |
circular |
Whether the grain is a circular loop or not. | float |
True / False |
end_to_end_distance |
UNKNOWN | float |
m |
basename |
Directory in which images was found. | str |
N/A |
image_stats.csv#
The image_stats.csv summarises the metrics
| Column / field / feature | Description | Type | Units |
|---|---|---|---|
image |
Filename of image statistics pertain to. | str |
N/A |
image_size_x_m |
Width of image. | float |
m |
image_size_y_m |
Height of image. | float |
m |
image_area_m2 |
Area of image (width x height). | float |
m^2 |
image_size_x_px |
Width of image in pixels. | int |
N/A |
image_size_y_px |
Height of image in pixels. | int |
N/A |
image_area_px2 |
Area of image in pixels squared. | int |
N/A |
grains_number_above |
Number of grains found above threshold. | int |
N/A |
grains_per_m2_above |
Density of grains above upper threshold. | int |
N/A |
grains_number_below |
Number of grains found below threshold. | int |
N/A |
grains_per_m2_below |
Density of grains below lower threshold. | int |
N/A |
rms_roughness |
Route Mean Square Roughness, the square root of the mean squared heights across the surface[^1] | float |
N/A |