Update app.py

app.py

@@ -134,6 +134,18 @@ def decompose_cavity(pred, th2=0.7, amin=10):
     
     return image_decomposed
 
+@st.cache
+def load_file(fname):
+    with fits.open(fname) as hdul:
+        data = hdul[0].data
+        wcs = WCS(hdul[0].header)
+    return data, wcs
+
+def change_scale():
+    del st.session_state["threshold"]
+
+
+
 # Use wide layout and create columns
 st.set_page_config(page_title="Cavity Detection Tool", layout="wide")
 bordersize = 0.6
@@ -149,29 +161,29 @@ with col:
     st.markdown("Input images should be centred at the centre of the galaxy and point sources should be filled with surrounding background ([dmfilth](https://cxc.cfa.harvard.edu/ciao/ahelp/dmfilth.html)).")
     st.markdown("If you use this tool for your research, please cite [Plšek et al. 2023](https://arxiv.org/abs/2304.05457)")
 
-_, col_1, col_2, col_3, _ = st.columns([bordersize, 2.0, 0.5, 0.5, bordersize])
+# _, col_1, col_2, col_3, _ = st.columns([bordersize, 2.0, 0.5, 0.5, bordersize])
 
-with col_1:
-    # Create file uploader widget
+# with col:
     uploaded_file = st.file_uploader("Choose a FITS file", type=['fits'])
 
-with col_2:
-    st.markdown("### Examples")
-    NGC4649 = st.button("NGC4649")
+# with col_2:
+#     st.markdown("### Examples")
+#     NGC4649 = st.button("NGC4649")
 
-with col_3:
-    st.markdown("<br>", unsafe_allow_html=True)
-    NGC5813 = st.button("NGC5813")
+# with col_3:
+#     st.markdown("""<style>[data-baseweb="select"] {margin-top: 26px;}</style>""", unsafe_allow_html=True)
+#     NGC5813 = st.button("NGC5813")
 
-# if NGC4649: uploaded_file = "NGC4649_example.fits"
-# elif NGC5813: uploaded_file = "NGC5813_example.fits"
+# if NGC4649:
+#     uploaded_file = "NGC4649_example.fits"
+# elif NGC5813:
+#     uploaded_file = "NGC5813_example.fits"
 
 # If file is uploaded, read in the data and plot it
 if uploaded_file is not None:
-    with fits.open(uploaded_file) as hdul:
-        data = hdul[0].data
-        wcs = WCS(hdul[0].header)
-    
+    data, wcs = load_file(uploaded_file)
+
+if "data" in locals():    
     # Make six columns for buttons
     _, col1, col2, col3, col4, col5, col6, _ = st.columns([bordersize,0.5,0.5,0.5,0.5,0.5,0.5,bordersize])
     col1.subheader("Input image")
@@ -182,7 +194,7 @@ if uploaded_file is not None:
     with col1:
         st.markdown("""<style>[data-baseweb="select"] {margin-top: -46px;}</style>""", unsafe_allow_html=True)
         max_scale = int(data.shape[0] // 128)
-        scale = st.selectbox('Scale:',[f"{(i+1)*128}x{(i+1)*128}" for i in range(max_scale)], label_visibility="hidden")
+        scale = st.selectbox('Scale:',[f"{(i+1)*128}x{(i+1)*128}" for i in range(max_scale)], label_visibility="hidden", on_change=change_scale)
         scale = int(scale.split("x")[0]) // 128
 
     # Detect button
@@ -192,7 +204,7 @@ if uploaded_file is not None:
     with col4:
         st.markdown("")
         # st.markdown("""<style>[data-baseweb="select"] {margin-top: -36px;}</style>""", unsafe_allow_html=True)
-        threshold = st.slider("Threshold", 0.0, 1.0, 0.0, 0.05) #, label_visibility="hidden")
+        threshold = st.slider("Threshold", 0.0, 1.0, 0.0, 0.05, key="threshold") #, label_visibility="hidden")
         
     # Decompose button
     with col5: decompose = st.button('Decompose', key="decompose")
@@ -203,8 +215,8 @@ if uploaded_file is not None:
     image = np.log10(data+1)
     plot_image(image, scale)
     
-    # if detect or threshold:
-    if st.session_state.get("detect", True)
+    if detect or threshold:
+    # if st.session_state.get("detect", True):
         y_pred, wcs = cut_n_predict(data, wcs, scale)
         
         y_pred_th = np.where(y_pred > threshold, y_pred, 0)